The Kuiper Belt could extend billions of miles farther than anyone thought. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. NASA's New Horizons ...

A distant gas giant the size of 10 Jupiters is now the first planet outside Earth's solar system to be mapped in three ...

Beyond the edge of Neptune, a distant realm of icy debris known as the Kuiper Belt stretches deep into space. This frozen frontier holds the scattered remains of the early solar system, offering ...

Their strange movements don’t match the predictions of current solar system models. This odd behavior has sparked new theories, including the bold idea that a yet-undiscovered Earth-sized planet may ...